This invention relates generally to apparatus for stirring grain, and more particularly to apparatus for stirring a mass of grain in a storage bin, the apparatus being generally of the type comprising a sweep arm disposed in a horizontal plane above the grain for being rotatably driven about the central vertical axis of the bin by a carriage on the outer end of the sweep arm engageable with a track extending around the inside of the bin wall, and a plurality of rotatable augers carried by the sweep arm and extending downwardly therefrom for stirring the grain in the bin thereby to aerate the grain to dry and blend it throughout the mass from bottom to top.
Reference may be made to applicant's U.S. Pat. No. 3,776,512 which shows prior apparatus for stirring grain on which the present invention is an improvement. Although the apparatus shown in that patent has been generally satisfactory, some problems have arisen, such as servicing the carriage at the outer end of the sweep arm (especially when the grain is stored in the bin), and the tendency of the carriage to jump off the track during the stirring process. The fact that the drive means for the vertical augers on the sweep arm has been largely exposed has also created certain safety problems.